Preheater for lighting and heating apparatus



April 14, 1942. MARQWSKY 2,279,924

- PREHEATEE FOR LIGHTING AND HEATING APPARATUS Filed Dec. 15, 1938.Zbzzepor mumrom x Patented Apr. 14, 1942 UNITED STATES OFFICE PREHEATERFOR- LIGHTING AND HEATING APPARATUS Max Marowsky, Berlin, Germany 4Claims.

The present invention has for an object to overcome difiiculties whichstill occur occasionally in preheaters employing comparatively narrowhair tubes for fuel admission and very wide air nozzles. With theemployment of such a hair tube, the inside diameter of which is at theutmost /5u of its length, disturbances in working occur occasionallywhich are caused by the fact that smuts, tinder or other residues fromthe manufacture of the hair tube become partly detached from the walland prevent the flow of the fuel. In accordance with the presentinvention, comparatively wide fuel feed pipes are used instead of verynarrow hair tubes, and the effective cross section of which is reducedby the introduction of an insertion pin in such a way that the sameproportion is obtained between the inside width and the length as in thecase of hair tubes referred to above. Moreover, an annular channel isprovided for the admission of air, in accordance with the presentinvention, in order to avoid the employment of an air nozzle, the mouthof which in the mixing chamber is located in the outlet direction beyondthe mouth of the fuel pipe, so that here i too the mouth of the fuelpassage in the mixing chamber is situated nearer to the outlet nozzlethan the mouth of the air passage.

The invention thus provides a preheater for illuminating and heatingapparatus fed by liquid fuel under air pressure, wherein an insertionpin is arranged in the fuel feed pipe, by means of which pin the crosssection of the feed pipe is reduced.

The invention is illustrated in the accompanying drawing:

Figure 1 of which shows in section an atomizer for a storm lantern orother illuminating or heating apparatus;

Figure 2 is a plan view of part thereof;

Figure 3 shows in section a modification in which the insertion pin isformed as a valve spindle;

Figure 4 shows a further modified form of the insertion pin;

Figure 5 shows a modification in which an atomizer preheater is arrangedunderneath the fuel reservoir; and

Figure 6 shows a modified form of the tubular piece which receives theinsertion pin.

In Figure 1 a fuel reservoir indicated at I has a thread nut 2 tightlysoldered thereto, a body 3 of the atomizer preheater being screwedtherein. This body 3 has at its lower end besides the exterior thread aninternal thread into which another body is screwed. The latter servesfor receiving a rising pipe 5 which is closed at its lower end by afilter 6 and accommodates in its interior an insertion pin 1. The body 4has a smooth or plain part the diameter of which is only a littlesmaller than the corresponding bore of the body 3,-and the thread of thebody 4 is interrupted locally so that an annular and very narrow channelis formed at the upper part-of the body 4 for the admission of air tothe mixing chamber 8. The body 4 is conically shaped at its upper end sothat the mouth of the fuel passage between thewall of the pipe 5 and theinsertion pin 1 therein is located nearer to the outlet opening than themouth of the annular shaped air channel in the mixing chamber 8. Theinsertion pin 1 is bent in the form of a hook at its lower end, in orderto prevent displacement thereof. This pin 1 is moreover bent once or anumber of times before insertion, in order to fit firmly within therising pipe 5 despite its smaller diameter. The valve body 9 has a borefor the valve spindle i0 and is at its upper end crowned by the outletnozzle II which in turn carries the flame pipe I 2. In the embodimentshown in Figure 3 the fuel feed or rising pipe I3 is formed withcomparatively large cross section and without an insertion pin. In thiscase an insertion pin la is constituted by an extension of a valvespindle la and is shaped at its front end as a slender cone I4 servingfor closing the outlet nozzle (5. The fuel pipe 5a is a press fit at itslower end in the body 3a. The insertion pin la, is loosely secured tothe spindle I0, so that it can be freely adjusted towards the'nozzle andprovide a tight closure. If the inserting pin 1a were rigidly connectedto the spindle In, it might be possible that the conical valve l4, wouldnot be co-axial with nozzle l5 and consequently no complete sealingwould be effected in closing the valve. The pin 1a is allowed sufiicientplay at the point of attachment to the spindle lflso that it may adjustitself in the axial position with regard to nozzle l5 to effectivelyseal the opening. It will be recognized that the conical surface of thepin 1a will render the same selfaligning. Th valve head is of a slenderand conical shape. The air channel [6 leads to an annular space of verysmall cross-section surrounding the tube 5a, which forms a continuationof the air channel, and the mouth of which latter is also further remotefrom the outlet nozzle l5 than the mouth of the fuel passage. Instead ofthe plain insertion pin la an insertion pin provided with a coarsethread, as illustrated at lb in Figure 4 can be-used, or alternativelyth fuel feed pipe 5 or 5a may be provided with an internal thread, asshown in Figure 6. The threaded surface provided on the pin lb servesthe purpose of extending the path of travel of the fuel flowing throughthe fuel feed pipe and further to increase the ratio between the lengthand the cross-section of the fuel feed pipe without altering theexternal digreater cross section than hitherto. By this means the dangerof obstruction is reduced to the utmost, but simultaneously the desiredthrottling of the air is obtained in a complete manner.

. .I claim:

1. A preheater for illuminating and heating apparatus fed by, liquidfuel under air pressure,

the direction of the admixture stream allows a still better regulationof the magnitude of the fiame. The slender conical formation of theinsertion pin Ia also helps to give a good regulating effect. Also thenew formation of the air channel as an annular channel contributesconsiderably to the good result. The new'atomizer is suitable also for ahanging arrangement,that is to say underneath thefuel' reservoir, forexample, for hanging lamps such as in the embodimentillustratedin Figure5. In the case of the latter' the tubular piece 5b is provided at itsrear end with externalf'and internal screw threads. The external threadis screwed into the'b'o'dy 3b and into the internal thread of the tube'55 the spindle "Illa is screwed only so far rearwardly'as' itabutsagainst' the ring I! which is inserted rigidly into the tubularpiece 5b, If the spindle llla'is'further rotated rearwardly the tubepiece 5b'is carried" along until the latter abuts the locking ring l8.The tubular piece 51) and the spindle Illa are conically shaped at theirfront end and formthus with corresponding edges on the n'oz'zle l9'andthe body 51), respectively, two valves tightening in the same direction, of whichthe inner one controls the fuel supply and 'the-outer' onethe air supply. In order to enable the'passage of the 'fuelthrough thering and the-spindle thread, the spindle 10a is formed mmagrowezotermmatmg before the' shutti ng o'fi' pointr The insertionpin 1e"hasat'its fi'ontn'd a cleaning needle 2|.

With this arrangement the external thread of p the tubular piece 517prevents a of the liquid level in a closed state.

withthearrangement in accordance with Figure 3 a compensation of theliquid level may take place'if this arrangement is employed so as to beplaced-underneath the fuel reservoir, so that on first opening the valvethe fuel discharges. But the-amount of escaping liquid quantity may belimited by appropriate choice of the dimensions of the air supplyingchannels so that the workingof the atomizer is thereby compensation notdisturbed.

The cross section of the fuel channel direct ly before the mouth in themixing chamber is of such dimensions that if circular-shaped thischannel will have a diameter which will be at the utmost 5a, of thelength of the fuel feed pipe 5, 5a or 5b as the case may be, so that thenozzle required at 'this' place which obviously will be more easilyobstructed, is replaced by a throttled pip'eilin'e of comparatively widecross'section, which'however, in regardto 'themode' of' executiori ofthe known arrangement have aparticular: advantage in that it'consists ofa tube with 'a substantially greater cross section which obviously canbe more easily keptcompletely clean internally and free frommanufacturing residues- In the same; manner thehitherto existing airnozzles aresubstituted 'by'a ring channel of a very small width, but;however, of considerably comprising in combination a reservoir for fuel,a valve body having an outlet nozzle and air and fuel passagescommunicating with the reservoir, a fuel feed pipe within the valve bodydefining an annular passage therearound for air, a valve stem ,in saidvalve body, an insertion pin in said fuel feed pipe reducing theeffective cross sectionalarea thereof and loosely secured at one end tosaid valvestem, a cleaning needle provided on the insertion pin for theoutlet nozzle.

'2. A preheater fo'r illuminating and heating apparatus fed byliquidfuel under air pressure, comprising in combination a reservoir for fuel,a valve, body having an outlet "nozzle and air and fuel passagescommunicating with.the reservoir, a fuel feed pipe slidablelongitudinally within the valve body and defining an annular passage forair therearound, a valve stem in said' valve body in co-axial threadconnection with the fuel feed pipe to shift the latter within the valvebody, towards and away from the outlet nozzle to close and open said'air passage, stops within the fuel feed' pipe toflimi't relative motionof said valve stem with respect to said fuel feed pipe, an insertion pinin said'fuel feed pipe reducing the effective cros s sectional areathereof and looselysecured at one'end to said valve stem and of slenderconicalshape at the'other end to close the'outlet nozzle to fuel.

'3. In a preheater forilluminating and heating apparatus fed by liquidfuel under air pressure, a valve body having an outlet nozzle and anaxial passage'therethrough, a pipe axially disposed within said passage,said pipe and said passage walls defining an" annular air spacetherebetweem an'axially adjustable valve stem in said valve'body; aninsertion pin secured at one' end 'to saidyalve' stem and extendingcoaxially through said pipe, said insertion pin being adapted to closesaid outlet nozzle, means for supplying air to said air space, and meansfor supplying fuel to said pipe.

4. In a preheater for heating and illuminating apparatus fedby liquidfuel under air pressure, a conduit to conduct the fuel to a mixingchamber, said conduitcomprising an elongated pipe of substantiallyconstant internal cross-sectional area throughout its length, aninsertion pin extending axially within said fuel pipe to reduce itseffective cross-sectional I rounding at least a portion of said fuelpipe but area, means Sl11-'

